Rubber printing-stamp.



PATBNTED AUG.14, 1906.

No. 82S." 4

L. R. BLAGKMORE.

RUBBER. .PRINTING STAMP.

APPLICATION FILED 0093.23. 1905.

2 SHEETS-SHEET 2.

lid/ii L s wl 1 LA @Wl I LAWRENCE E. BLACKMORE, OE ARLlNGTON,

lirlE@` STAEES PATENT EECE@ NEW ausser, Assieuon TO THE BLACKMORE ENGINEERING COMPANY, OF ARLNGTON, NEW JERSEY, A CORPURATIN OF NEW JERSEY no. sesgos Specification oi' Letters Patent.

Fatented Aug. 1li', 1906.

pplication tiled October 23, 1905. Serial No. 283906,

To LLL whom. it may concern.-

.at Arlington, Essex county, State of New Jersey, have invented certain new and useful improvements in Rubber Printing-Stamps, of which the following is a specification.

Myimproyemen ts relate to the specific construction' of the blank rubber strips from which Sensible l silient bases 'for rubber types are made, es w es to the bases themselves, said bases being interposed between the types and the stamp-blocks for the purpose oi' ai"- ordin a medium ci support which will equalivze an distribute pressure and insure a perfeet printing contactl under the varying conditions of use.

The object of my invention is to increase the sensitiveness and flexibility of each base While maintaining the requisite degree of resiiience ant1 e time to c ord a base Athe Whole s e of which pi'uctically a smooth con nous nonnbsorbent shin of close impervious texture.

To this end the invention consists, primarily, in a blanif` strip of rubber formed with a series of hollow columns havingintersecting ooves between them, hollow columns eing connected by very narrow thin webs vorinii'ig the bottoms oi said intersecting grooves and constituting convenient lines oi 'of a suitable stamp-block and rubber severance, whereby a portion of the strinof suitable aree and shape may be detached to form a type-base, the said lines of severan e being practically coincident wi th the external side Walls of the columns, so that there isno marginal Waste of web or protrusion ther-soif beyond the outer circumscribingwalls of the base thus formed. Incidentally 'the invention includes the combination with such bese printing-types and in certain other features hereinafter described and claimed specifically.

An important feature in the manufacture of my blank rubber strip consists informing it in a mold -having intersecting partitions With'sharp couver entedges which extend to the skin forme by the contact of the rubber With-the opposed surface oi the mold, as hereinafter set forth, by. which means the sides of adjoining hollow columns converge and meet in a sharp Well-deiined line of severance, so that When an incislon 1s made through the web along one of these lines of severance the new surfaces exposedwill not only form continuations of the external side Wells of the columns, but will also be found to be as smooth and im erforateas said Walls of the column, thus a Ording a continuous unbroken non-absorbent surface throughout the type-base. At the same time this skin Web is of sufficient thickness and strength to hold the hollow columns together under 0rdinary conditions of stora e, transportationf or manipulation and until iorcbly severed by a sharp instrument for the purpose above set forth. Thus practically any number of the hollow columns may be detached from the strip to form a bese of any desired configuration and dimensions, restricted only by the length end breadth of the strip and the size of .its hollow columns without opening up or exposing the internal structure of the rub ber. l thus attain an individual stamp base or backing of exceptional resilience, since the hollow columns constituting n series of sealed air-cel` Vhen attached to the stamp-bloeit and quick adapting then".H c to variations in pressure, i the sinne time the bas Without trimming or al preperaon, siiords a continuous urii i external shin or surface Wl ch presen ts av symmetrical appearance, prevents ab sorption of iuli', dirt, or extraneous matter of any hind, and protects the internal relatively soft porous texture of the rubber against the otherwise deteriorating iniiuences of the atmosphere.

is to be understood that l do not restrict myself to any particular shape in cross-sec tion of the hollow columns into which the strip is subdivided by the intersecting seven ing-grooves provided the connecting-webs et the bottom oi the latter are of less width and thickness than the 'Walls of said hollow' coldo not exceed in thickness that of unms 'i the sl 1i union to 'the Whole surface of the strip,y Thus instead ci e series of hollow cun vbic columns with grooves between them they sides of which are 'essentially vertical the hollow columns ma 1' he of truncated vpyrenmlal torni, the resultingsevering-grooyes with 1mclined convergent sides meeting at a sharp angle in the web at the bottom of said grooves, thereby providing an ideal line of severance, while the width of such grooves aHords ample scope for the lateral and individual expansion of the hollow columns. This freedom of individual lateral expansion of the hollow columnsv by reason of the intersecting severing-grooves adds materially to the flexibility 1o -and resilience of the base, enabling it, in part or in whole, to adapt itself more readily to any and all inequalities of surface to which the printing-types may be applied. '1

' In the accompan 'ng drawings, Figures 1 and 2 are respective .y side and end views of a hand-stamp embodying the essential features of my invention. Fig, 3 is an isomet rical perspective showing a blank strip form d with hollow cellular columns. Figs. 4 and zo are respectively top and bottom. views of a base severed from the strip shown in Fig. 3. Fig. 6 is a transverse section upon plane of line 6 6, Fig. 4. Fig. 'Tis a transverse section upon plane of line 7 7 Fig. 6. Fig. 8 is a sec- `2 5 tional detailillustrating the. bending of the strip on one of the lines of severance. Fig. 9 shows da ammatically a portion of a strip having co umns in the form of rectangular parallelograins.y Fi 10 is a similar view 3o showing1 the lines o" severance crossing -the strip 11, a similar view agonally, Fi showing columns of rhomboidal shape. Fig. `12 is an isometrical view `of a portion' of a strip having columns of truncated pyramidal 3 5 shape; Fi 13, a top view of the structure shown in' ig. 12. Fig. 14 is a top view of a portion of a matrix used in the manufacture of the stri shown in Fi s. 3 to 8, inclusive, the parts eing materially enlarged for con 4o venience of illustration. Fig. 15 is a view showing a portion of the matrix used in the manufacture of the strip illustrated in Figs. 3 to 8, inclusive. Fig. 16 is a section upon plane of line 16 16, Fig. 15. Fig. 17 is a view showing the form of matrix used in the manufactureof the strip shown in 12, 13, and 14. Fig. 18 is a section upon plane of line 18 18, Fig. 17.

In the drawings, A represents a stamp- 5o block of any ordinary or desired construction provided with a handle a. 'Io the face c of -this stamp-block A. is attached the exible resilient type support or cushion or base B, which forms the essential feature of my in- 5 v'ention.

'The base B may be attached directly to \the.fa'ce a. of the stamp-block A or indirectly through the medium of a sheet or layer c of rubber or other suitable material interposed 46o between the face a. of the stamp-block at any y stage in the manufacture of the stamp as a whole.y The rubber type T are attached, preferably, to the bottom or continuous web of the base B, although this is not essential.

surface or pressure.

scarce The type cushion or base B consists of 'a section of a blanlr strip S of the required size formed ,by cutting the connecting-web w at the bottom of the severing-groove g. These severing-grooves g are created by intersecting partitions m m in the matrix M, used in manufacture of the strip SI-sucln for instance, as the rectangular partitions shown by way of illustration upon a greatly-enlarged scale in Figs. 15 to 18, inclusive, by reference to which it will be seen that the edges of the partitions are preferably sharp or convergent, so as to form very narrow bot toms to the gr oves g, thus creating very thin well-define lines for' the severance of the web w of the blank strip. In fact, this narrowing of the bottom of each severing# groove g to a sharp thin line meeting or extending into the slrin formed by the contact ,of the rubber with the inner surfaces of the mold is an important factor in the construction of the blank strip S, since I thereby attain a line of severance which leaves no margin or selvage and which does not open up er expose the internal structure of the strip S or of the g type-base B made therefrom. By preference the partitions, even for the forms of strip shown 1n the Vfirst eleven views ofthe drawings, are made convergent or knifeshaped in cross-section, so that the difference between the partitions shown in Figs. `15` and 16, as comparedwith those shown in Figs. 1'7 and 18, is essentially onl` one of breadth of base, although the co umns d, v

formed on the strip S by t ie partitions fm, are

in the first instance mentioned practically square and uniform in dimensions, while in the latter instance they are in the form of truncated pyramids. In either case I attain my object in the creation ofa tough but thin nar row ligature'or well-defined line of severance at the bottom of the groove g and between the opposed sides thereof that will result in Aclean compact air-tight and non-absorbent edges on either side of thecut. The grooves g, to a greater or less extent in proportion to the degree of convergence or space between their opposed side walls, also perform ann IOO' Irc

other important function in that they aord i scope for individual lateral ex ansion by and between the columns d, whic is important because it increases and renders more uniform and responsive the fle'ggibility of the type-b ase B, so that the inner or central portion thereof will yield as readily as the marginal portibns, and thus allow the rubber types to adapt themselves more readily to `merpialities of umns d obviates very' lar ely any danger of cellular rupture under undue pressure.

In order to attain a relatively higlh degree of elasticity and resilience, I mol Acells d within the columns d, Said cells d being Furthermore, this prcvision for the lateral expansion of the I'col.

.las

seat/oe closed and hermetically sealed by the face a of the stamp-block. or by the facing c of rubber or other soft elastic material interposed between the face a/ oiE said block A and the base B, the case may be.

Dbviously the intersecting lines oi' severance g between the hollowvcolumns d are arranged to the best advantage when extended longitudinally and transversely of thestrip S and at right angles to each other, as waste of material is thus avoided, since the elastic type cushions or bases B usually required'are of elongated rectangular lorrn. At the same time other arrangements of the intersecting lines of severance g may be resorted to with-- out departing from the spirit and intent of my invention by which l afford a blank strip S, Jfrom which practically a type-base B of any desired length and width may be quickly and conveniently cut, said being then ready for immediate application and use and being complete and perfect in all its parts, with a continuous hermetically-sealed surface and with no protuberances or roughness of surface. Hence the internal structure is eiieetually protected against the deteriorating effects of the atl'nosphere, there canbe no absorption or contamination, and a smooth external surface is afforded which can readily be kept clean.

What l claim as my invention, and desire to secure by Letters Patent, is-

i. In a hand-stamp, the combination with the stamp-block of a rubber type-base attached thereto consisting of an integral strip of rubber formed with intersecting grooves with hollow columns between them, said hollow columns being united at the bottom of the said intersecting grooves by thin narrow webs of less wid th than the thickness of the side walls of said hollow` columns, said webs consisting of the skin at the bottom of said intersecting grooves, and all the surfaces of the blank being -iermed with a smooth continuous surface, together with a rubber type plate attached to the rubber type-base.

2. in a hand-stamp, the combination with the stamp-block of a rubber type-base attached thereto consisting oi' an integral strip oi' rubber formed with intersecting grooves with hollow columns between them, said hollow columns being united by a web consisting of the skin at the bottom of the said interseeting grooves, the sides of which latter extend down to said skin" where they intersect each other, so as to form sharp and Welldefined lines of severance for the purpose described, together with a rubber type-plate attached to the said rubber type-base.

3. As an article oi" manufacture, a handstamp eonsistin of a rubber t pe-plate mounted upon a ollow flexible rub er cushion formed with a ci adjoining cells having independent side walls the opposed sides of said adjoining cells being united. by thin. narrow webs consisting of the skin at the base oi the cells, said webs being of less width than the thickness ot the cell-walls and the edges oi said walls being attached to the stamp-block, together with said stamp-block, for the purpose described.

4. AChase-plate for hand-stamps consisting et an integral strip oi' rubber 'formed with parallel se, es oi independent hollow columns united by webs or ligatures ot less width than the thickness oi the walls of the hollow columns, for the purpose described.

5. A b ase-plate for hand-stamps consisting of an integral strip ot rubber :termed with parallel series olf independent hollow columns which are cuadrangular in cross-secl'tion united by webs or ligatures ot width than the thickness of the walls oi said hollow columns, for the purpose described.

6. A molded blank for rubber type-bases consisting of an integral strip of rubber formed with two series of parallel severinggrooves, one series intersecting the other, with hollow columns united by thin narrow webs of less width than the thickness of the walls of the columns, said webs consisting of lthe skin at the bottoms of said. intersecting grooves.

7. A molded blank i'or rubber type-bases consisting of an integral strip of rubber formed with two series ot parallel sei-"cringgrooves intersecting each other at right angles, with hollow quadrangular columns united by thin narrow webs of less width than the thickness of the walls of said hollow quadrangular columns, said lwebs consisting of the skin .at the bottom of said intersecting grooves y 8. A molded blank for rubber type-bases consisting of an intevral strip oi rubber formed with a series et longitudinal parallel severing-grooves"and a series of transverse parallel severing-grooves, with square hollow columns between them united by thin narrow webs of less width. than the thickness of the walls'oi said square hollow columns, said webs consisting of theskin at the bottom of said intersecting grooves.

9. A molded blank for rubber ty e-bases consisting of an integral strip o rubber formed with two series of parallel severinggrooves, one series intersecting the other,

' with hollow columns between them united by webs consisting of the skin at the bottoms of said intersecting grooves the sides ci which extend down to said skin" where they intersect each other to term sharp welldeiined lines of severance, for the purpose described.

10. A molded blank for rubbertype-bases IOC consisting of an integral strip of rubber sect it and each other to form sharp Well-deformed with two series of parallel grooves, fined. lines of severance for the purpose deone series intersecting the other, with. ook scribed. umns between 'them united by Webs oorlsist- LAWRENCE R. BLACKMORE.- ing of the skin at the bottoms of said in- Witnesses: f 1 teraeotng grooves the sides of which latterv D. W. GARDNER,

extend down to the said. skin and. inter- Grao. WM. MIATT. 

